1. Field of the Invention
The invention relates to an electrical contact element, in particular a contact element formed as pin contact or socket contact, having a plug region and a terminal end for connecting an electrical conductor.
Such a contact element, which is as a rule surrounded by an insulating housing, is needed in order to make an electrical connection between an electrical conductor and a terminal end of an electrical pin contact or of a socket contact, without, however, any special tool being necessary.
2. Description of the Prior Art
A number of connection principles are known in technology for connecting electrical conductors to a contact element, such as by means of soldering, by means of screw terminals, by a cage clamp terminal or alternatively by crimp terminals.
DE 199 14 308 A1 discloses an electrical terminal unit having a housing, in which at least one terminal for an insulated conductor or a stripped conductor is provided that has at least one cutting element and at least one spring element.
Disadvantages in such cases are that various connecting principles, such as, for example, soldering, are steadily losing ground in industrial connecting technology because of the expense, and that screw terminals as well as cage clamp terminals have a relatively large space requirement and crimp terminals always require a special tool.
The object of the invention is therefore to construct a contact element of the type mentioned at the outset in such a way that at least one contact element that is already in use and has a crimp or screw terminal can be replaced by or exchanged for the contact element according to the invention without difficulty, at least comparable contacting data, such as contact resistances and gastight connecting points between an electrical conductor and a contact element, being achieved with this connecting technology to that in the case of a crimp terminal, but without needing the special tool, for example a crimping tool.
This object is achieved in that a sleeve can be mounted on the terminal end, in that the sleeve has spring arms stamped out of its wall and directed into the sleeve interior, and in that the spring arms enter a bore in the terminal end of the contact element.
Advantageous embodiments of the invention are specified in claims 2-5.
The advantages achieved by the invention are, in particular, that the outer contours of such contact elements formed as pin or socket contacts are adapted to already existing plug connector systems that are in use and, consequently, older versions that are provided with a crimp, screw or solder terminal can readily be replaced, without a special tool of any kind being needed. In addition, almost identical conductor pull-out forces are achieved with this type of attachment as in the case of a screw terminal.
Furthermore, it is advantageous that the terminal cross section of the electrical conductor for the contact element according to the invention covers a greater range of variation than is possible in the case of a crimp terminal; thus, in total, cross-sectional areas of 0.5 to 2.5 mm2 are connectable. As a result of the formation of a sawtooth thread at the terminal end of the contact element, the wedge action of the tips of the spring arms exerted on the electrical conductor is advantageously achievable not only by a rotary movement, but also, optionally, by an axially latching action of the sleeve. The wedge action of the spring arm tips achieves, in addition, a vibration-proof and extraction-proof attachment technology for the electrical conductor.